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61.
运动发酵单胞(Zymomonas mobilis)ATCC29191菌株在含1~3g/L甘氨酸的液体培育12小时的菌体,用含20g/L的溶菌酶溶液处理12小时,可以稳定得到80%~90%的原生质球。原生质球稀释后在底层再生培养基上涂布,上面复盖一层半固体培养基,30℃培养5~7小时,再生率可达10~(-2)水平。  相似文献   
62.
乙烯分离技术分析   总被引:3,自引:0,他引:3  
王振维 《乙烯工业》2004,16(3):40-43
从技术先进性、能耗、流程复杂性和运行稳定性等诸多方面对占据乙烯市场的三大分离技术进行了分析。并认为用户在选择分离技术时应综合考虑各方面因素,把握重点,选择出适合的技术。  相似文献   
63.
纤维素酶的固体发酵   总被引:3,自引:0,他引:3  
从来自国内外11株菌株的初步比较,筛选出酶活较高的康氏木霉N_2—78和瑞热埃木霉QM6a。对康氏木霉P_2和土曲霉3.3935所作的纤维素碳源试验中,发现木质纤维素较纯纤维素好,未经处理的木质纤维素比经处理的好。麸皮和稀土对康氏木霉P_2产酶作用影响较大,而对土曲霉3.3935则无明显的影响。  相似文献   
64.
On basis of adopting polygeneration systems for power and alternative fuels,capturing CO2 with near zero energy penalties,and storing CO2 on sites,a new kind of Energy Network can integrate energy utilization,CO2 capture,transportation and storage synthetically.Techno-economic analysis of this solution focusing on Inner Mongolia and the Yangtze River Delta districts had been carried with comparison to the chain method for energy utilization and CO2 sequestration.This solution can save 21.5% of energy,and re...  相似文献   
65.
We presented the analysis of the incomplete conduction in bonding medium in high power GaN-based light-emitting diode (LED) packages. A numerical study was carried out with parametric model to understand the junction temperature variation due to bonding medium defects. Transient thermal measurement was performed to evaluate LED’s junction temperature. Thermal resistance from chip to lead frame was 20 K/W in our sample LED. It was suggested that only 60% of the surface area of the bonding medium was involved...  相似文献   
66.
Microgrooves were prepared on Si(100) surface by photolithography and wet etching.Subsequently,Si-N-O films were deposited on the microgrooves by unbalanced magnetron sputtering(UBMS) and micro-patterned surfaces of Si-N-O films were obtained.The size of the micropatterns was measured by surface profilometer.The chemical composition of Si-N-O films were characterized by X-ray photoelectron spectrometry(XPS) and the wettability of the micropatterned surfaces was evaluated by contact angle measurement.The beh...  相似文献   
67.
A novel double suction shaft-less mini pump was developed for heat control of small energy systems in this study.The mini pump impeller with an exit diameter of 40 mm was combined with the motor rotor supported by the hybrid dynamic bearing.The specific speed of the pump was 125 min-1 m3 min-1 m.The hydraulic performance of the pump was investigated experimen-tally under four rotational speeds.From the test results,it was recognized that the pump could provide a flow discharge of 5 L/min and head of 1.5 m,w...  相似文献   
68.
Combustion tests of pre-mixture of methane and air in constant volume combustion chamber(CVCC) have been carried out by means of flame propagation photo and gas pressure measurement,the effects of CVCC body temperature,intake pressure of pre-mixture of methane and air,equivalence ratio and location of the built-in adaptor have been investigated.The whole combustion chamber can be divided into two parts,i.e.the upper combustion chamber and the lower combustion chamber,by the built-in adaptor with through hol...  相似文献   
69.
The existing equivalent methods usually only deal with static load models and neglect the dynamic characteristics of loads such as induction motors.This paper presents a dynamic equivalent method which considers motor dynamics.At first,the clustering criterion of motor loads is given.The motors with similar dynamic characteristics are classified into one group.Then,reduction of motors in the same group is carried out.Finally,parameters of the equivalent motor are calculated and the equivalent system is thus...  相似文献   
70.
Ejector can utilize high pressure energy from liquid mechanism,it can be used in heat pump system coupled with economized vapor injection(EVI)scroll compressor.When running under low temperature conditions,the performance of the EVI system with ejector can be improved further.In this paper,the design method of the heat pump system with ejector is presented,and the process for designing the heat pump with ejector(EVIe)was summarized.One prototype heat pump was designed under the condition of the evaporation ...  相似文献   
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